title: Hepatitis B vaccination of men who have sex with men in the Netherlands: should we vaccinate more men, younger men or high-risk men?
abstract: OBJECTIVE
  The selective vaccination programme against hepatitis B virus (HBV) was introduced in the Netherlands in 2002 targeting high-risk groups, including men who have sex with men (MSM). Despite the high average age of vaccination in MSM, the number of notifications of acute HBV recently declined. We investigate whether this can be attributed to the selective vaccination programme. We examine how vaccination strategies could be improved and the impact of universal infant vaccination introduced in 2011.
  
  
  METHODS
  We use a mathematical model for HBV transmission among MSM. The incidence of HBV was calculated from the model and from notification data of acute HBV.
  
  
  RESULTS
  A decline was observed in the incidence of HBV since 2006, as calculated from the model; this decline was smaller than that observed in data if all MSM were equally likely to be vaccinated. Assuming that high-risk MSM were more likely to be vaccinated than low-risk MSM resulted in a steeper decline in modelled incidence and better agreement with observed incidence. Vaccinating MSM at a younger age or doubling the vaccination rate would increase the impact of selective vaccination, but is less effective than vaccinating high-risk MSM.
  
  
  CONCLUSIONS
  Selective HBV vaccination of MSM in the Netherlands has had a substantial impact in reducing HBV incidence. The reduction suggests that vaccination rates among high-risk MSM were higher than those among low-risk MSM. Countries that have not yet reached 35-year cohorts with universal childhood vaccination should actively implement or continue selective high-risk MSM vaccination.
authors.affiliation: Centre for Infectious Disease Control, National Institute of Public Health and the Environment, , Bilthoven, The Netherlands.
authors.forename: Maria
authors.initials: M
authors.lastname: Xiridou
authors.forename: Robin
authors.initials: R
authors.lastname: van Houdt
authors.forename: Susan
authors.initials: S
authors.lastname: Hahné
authors.forename: Roel
authors.initials: R
authors.lastname: Coutinho
authors.forename: Jim
authors.initials: J
authors.lastname: van Steenbergen
authors.forename: Mirjam
authors.initials: M
authors.lastname: Kretzschmar
mesh_terms: D006509:Hepatitis B / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D017325:Hepatitis B Vaccines; D018451:Homosexuality, Male / Q000706:statistics & numerical data; D006801:Humans; D017589:Immunization Programs; D015994:Incidence; D008297:Male; D008962:Models, Theoretical; D009426:Netherlands; D018579:Patient Selection; D011159:Population Surveillance; D018570:Risk Assessment; D012307:Risk Factors; D012725:Sexual Behavior / Q000706:statistics & numerical data*
chemical_list: D017325:Hepatitis B Vaccines
keywords: Hepatitis B; Mathematical Model; Men; Vaccination